Hypoxia-inducible factor 1α regulates branching morphogenesis during kidney development

The kidneys are exposed to hypoxic conditions during development. Hypoxia-inducible factor (HIF), an important mediator of the response to hypoxia, is believed to have an important role in development. However, the relationship between HIF and branching morphogenesis has not been elucidated clearly.     

A Theoretical Model of Jigsaw-Puzzle Pattern Formation by Plant Leaf Epidermal Cells

Plant leaf epidermal cells exhibit a jigsaw puzzle–like pattern that is generated by interdigitation of the cell wall during leaf development. The contribution of two ROP GTPases, ROP2 and ROP6, to the cytoskeletal dynamics that regulate epidermal cell wall interdigitation has already been examined; however, how interactions between these molecules result in pattern formation remains to be elucidated. Here, we propose a simple interface equation model that incorporates both the cell wall remodeling activity of ROP GTPases and the diffusible signaling molecules by which they are regulated. This model successfully reproduces pattern formation observed in vivo, and explains the counterintuitive experimental results of decreased cellulose production and increased thickness. Our model also reproduces the dynamics of three-way cell wall junctions. Therefore, this model provides a possible mechanism for cell wall interdigitation formation in vivo.     

Regional localization of the hepatocyte growth factor (HGF) gene to human chromosome 7 band q21.1.

Hepatocyte growth factor (HGF) is a polypeptide involved in liver regeneration. Its amino acid sequence and gene structure are similar to those of coagulation-related serine proteases. We have used a cDNA clone of HGF and flow-sorted human chromosomes to assign this gene to chromosome 7. Fluorescence in situ hybridization of the HGF genomic clones to human metaphase chromosome spreads showed the localization of this gene to 7q21. Estimation of fluorescent signals relative to arbitrary reference points (ARPs) allowed further localization to 7q21.1.     

Effects of MSH on food intake, body weight and coat color of the yellow obese mouse

Viable yellow obese mice (Avy/a) were treated for 10 days with 5, 15, 50 or 150 micrograms/d of either alpha-MSH or desacetyl-MSH. The half-maximal effect on weight gain occurred with a dose of 5 micrograms/d for desacetyl-MSH and at a 30 fold higher level of 150 micrograms/d for alpha-MSH. In contrast, the half-maximal stimulation of eumelanin production by alpha-MSH occurred at 15 micrograms/d and with desacetyl-MSH at 150 micrograms/d, a 10-fold increase. Desacetyl-MSH produced a dose-related increase in the weight of muscle, as well as white and brown adipose tissue. Desacetyl-MSH and alpha-MSH both increased plasma corticosterone concentrations, but desacetyl-MSH was more potent. In a 2 x 2 factorial designed study, body weight was significantly increased in viable yellow mice only by treatment with desacetyl-MSH but in the lean animals, both alpha-MSH and desacetyl-MSH increased body weight. Food intake was significantly different between genotypes, and was stimulated by desacetyl-MSH. These studies demonstrate potent differences in biological actions on food intake, body weight, and a variety of organ weights between acetylated and desacetylated forms of MSH.     

Assignment of a human serum glycoprotein SP-40,40 gene (CLI) to chromosome 8.

SP-40,40 is a serum glycoprotein consisting of two different subunits (alpha and beta) assembled into a dimer by disulfide bonds. Northern blot hybridization, using total RNA from several cell lines, showed that SP-40,40 is expressed in glioblastoma and testicular tumor cells, as well as hepatoma cells. Spot blot hybridization of flow-sorted human chromosomes, using a SP-40,40 cDNA fragment as a probe, localized the gene for SP-40,40 to human chromosome 8. This gene has been given the designation CLI, for complement lysis inhibitor, by the Human Gene Nomenclature Committee.     

Embigin/basigin subgroup of the immunoglobulin superfamily: Different modes of expression during mouse embryogenesis and correlated expression with carbohydrate antigenic markers

Embigin and basigin are highly glycosylated transmembrane glycoproteins with two immunoglobulin domains and form a subgroup in the immunoglobulin superfamily. Previous studies have demonstrated the functional significance of these molecules. In the present study, in situ hybridization analysis of their expression was performed during mouse embryogenesis. Embigin was strongly expressed in the endoderm during early postimplantation embryogenesis, and in the somite stage in the gut and visceral endoderm. Embryonic ectoderm and its derivative tissues weakly to moderately expressed this molecule. From day 10 to 15 of gestation, no embigin signal was detected. Basigin was more broadly expressed. During the organogenesis period, basigin was expressed in various epithelial tissues, brain ventricles, the spinal cord and dorsal root ganglion. The modes of expression of these two proteins throughout the egg cylinder stage correlated with the expression of the carbohydrate markers that they carry; embigin with Dolichos biflorus agglutinin binding sites and basigin with Le^x antigen and more closely with fucosyltransferase IV, which forms the antigenic epitope. These findings imply that proteins with specific carbohydrate epitopes play roles in early postimplantation embryogenesis.